Top drive with automatic positioning system

ABSTRACT

An automatic top drive positioning system includes a top drive having a pipe handling system rotator gear, a drive motor rotationally coupled to the rotator gear and a rotational position sensor rotationally coupled to the rotator gear. A controller is configured to operate the drive motor to automatically move the rotator gear to a selected rotational orientation based on measurements from the rotational position sensor.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND

FIG. 1 illustrates a top drive system 10 which is structurally supportedby a derrick 11. The top drive system 10 has a plurality of componentsincluding a top drive 14, (shown schematically) a main shaft 16, ahousing 17, a drill string 19 and a drill bit 20. The components arecollectively suspended from a traveling block 12 (moved by a “drawworks”not shown) that allows them to move upwardly and downwardly on rails 22connected to the derrick 11 for guiding the vertical motion of thecomponents. Reactance to torque generated during operations with the topdrive or its components (e.g. during drilling) is transmitted throughthe rails 22 to the derrick 11.

The main shaft 16 extends through the motor housing 17 and connects toitems below the shaft (“stem” or “shaft” can include stems and shafts).The shaft 26 may be non-threadedly connected to an upper end of an IBOPassembly 24 which is the first in a series of items and/or tubularmembers collectively referred to as the drill string 19. An opposite endof the drill string 19 is threadedly connected to a drill bit 20.

During operation, a motor 15 (shown schematically) encased within thehousing 17 rotates the main shaft 16 which, in turn, rotates the drillstring 19 and the drill bit 20. Rotation of the drill bit 20 produces awellbore 21. Drilling fluid pumped into the top drive system 10 passesthrough an interior passage or conduit in the main shaft 16, the drillstem 18, the drill string 19, the drill bit 20 and enters the bottom ofthe wellbore 21. Cuttings removed by the drill bit 20 are cleared fromthe bottom of the wellbore 21 as the pumped fluid passes out of thewellbore 21 up through an annulus formed by the outer surface of thedrill bit 20 and the walls of the wellbore 21. A typical elevator 29 issuspended from the top drive system to perform “pipe tripping”operations as will be explained in more detail.

A variety of items can be connected to and below the main shaft 16; forexample, and not by way of limitation, the items shown schematically asitems 24 and 26 which, in certain aspects, and not by way of limitation,may be an upper internal blowout preventer 24 and a lower internalblowout preventer 26. In other systems according to the presentinvention the item 24 is a mud saver apparatus, a load measuring device,a flexible sub, or a saver sub. A connection assembly 40 cannon-threadedly connect the item 24 to the main shaft 16. The shaft 16may be a drill stem or a quill.

In typical top drive drilling operations, top drive elevators 29 are setto have a pipe handler (explained below) oriented in one rotationaldirection to trip pipe (move the drill string into and out of thewellbore) and in another for drilling. The trip pipe orientation limitsthe extension travel of the elevators 29. Limiting the elevatorextension allows the elevators 29 to clear a racking board 42 and/orparts in relation to the racking board 42, and this may include parts ofthe derrick 11. Such orientation allows the top drive 10 to travel up toor down from the racking board 42 and crown (top of the derrick 11)without the possibility of interference between the top drive pipehandling equipment and other items. The tripping rotational orientationalso allows the elevators 29 and associated pipe handling equipment toextend out as close as possible to the derrick man/racking board 42without interference between the elevators 29 and racking board 42 orthe derrick 11. Height of the top drive system 10 above the derrickfloor may be determined by any known type of sensor 41, either indrawworks (not shown) or other convenient location proximate the derrick11.

There is a pre-determined “safe” zone of pipe handler rotationalorientation in which the top drive and pipe handler can be rotated froma preset “trip” position. The safe tripping zone allows the pipe handlerto be orientated in various trip positions to allow ease of pipehandling, including inserting and removing pipe to/from the elevators 29for tripping pipe in and out of the wellbore without the risk of makingcontact with the racking board and/or other parts of the derrick 11.

There is also a predetermined “drilling position”, ordinarily oriented180 degrees from the “zero” or pipe trip position, which allows theelevators 29 to be retracted far enough to allow the top drive system 10to reach the drill floor without the elevators interfering with thedrill floor. In such retracted position it is possible for the elevators29 to make contact with the racking board 42 if the top drive system 10were lifted sufficiently, so without proper monitoring, hoisting orlowering the top drive system 10 can result in damage to equipmentand/or personnel.

In ordinary drilling operations, the top drive system 10 is hoisted upto the elevation level of the racking board 42 using the drawworks andthe top drive pipe handling system, a “stand” of drill pipe can then beextended out to an operator situated in the derrick (the “derrick man”)and rotationally orientated based on hand signals and/or radio signalsto the drilling unit operator (“driller”) as to orientate the elevatorsin the precise direction needed for ease of the derrick man to installor remove pipe to/from the elevators. The precise location that theelevators need to be rotated to depends on which side of derrick 11 thepipe is being racked or removed from as well as factors such as theconfiguration of the derrick. The pipe handling system can be rotatedfrom the trip position to the drilling position to allow the top driveto move all the way to the drill floor with the elevators retracted(extended close to horizontal) to prevent the elevators 29 fromcontacting the drill or derrick floor.

Using hand signals or radio signals to communicate between the derrickman and the driller can be inefficient and sometimes dangerous. Thereexists a need for an automatic system to determine rotational positionof the pipe handling portions of a top drive, and automatic controls toprevent unsafe orientation and positioning of the various top drivecomponents during operations.

SUMMARY

One aspect of the invention is an automatic top drive positioning systemincluding a top drive having a pipe handling system rotator gear, adrive motor rotationally coupled to the rotator gear and a rotationalposition sensor rotationally coupled to the rotator gear. A controlleris configured to operate the drive motor to automatically move therotator gear to a selected rotational orientation based on measurementsfrom the rotational position sensor.

Other aspects and advantages of the invention will be apparent from thedescription and claims which follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a top drive in a drilling unit derrick.

FIG. 1 shows an example control screen for an automatic pipe handlingsystem.

FIG. 2A shows an oblique view of an example top drive according to theinvention.

FIG. 2B shows another view of the example top drive.

FIG. 3 show an example block diagram of an automatic system according tothe invention.

DETAILED DESCRIPTION

A top drive with automatic pipe handing system may be used in a derrickas explained with reference to FIG. 1A. FIG. 1 shows an example operatorconsole or control panel 103 that may be used with a system according tothe invention. The operator console 103 may be a “touch screen” such asone sold by GE Fanuc Automation Americas, Inc. or similar control panel,although the type of control panel or operator console is not alimitation on the scope of the invention. The example operator console103 shown in FIG. 1 may include certain displays and controls asfollows. At 100 the top four “buttons” or touch screen windows mayactivate “set” positions so an automatic pipe handler (explained withreference to FIGS. 2A and 2B) will automatically stop rotation at anyrotational position selected. At 102, during power up the drilling unitoperator (“driller”) may acknowledge, by pressing a suitable controlwindow on the touch screen (or an actual switch or electronic controlbutton, for purposes of the invention any such device is usable, theinvention is not limited by the type of operator console or diplay) thatthe pipe handler rotational orientation matches the orientationdisplayed by an indicator 101, which may be an actual gauge or may be acomputer display or combination display/touch screen. At 104 a gauge onthe operator console 103 may display the actual rotational position ofthe pipe handler with reference to the indicator 101. Error messages mayappear on the display if there is an error, e.g., if the pipe handler isin an incorrect rotational position with respect to its elevation abovethe drill floor. At 106 a control may be provided on the operatorconsole or control panel to “unlock” the pipe handler and allow theautomatic positioning system to function. At 108, two arrow keys shownon the example operator console may be used to choose the direction torotate the pipe handler. At 110, a control window or button on theoperator console may be provided to select between manual and automaticoperating mode. At 112, a calibration control may be provided. Forexample, a system controller (see FIG. 3) may be programmed such thatwhen the button or window shown is actuated for a selected time (e.g., 2seconds) to set the pipe handler actual position to zero when the pipehandler position is actually at zero degrees. Zero degrees may bedefined as the above described trip position, although it is to beunderstood that any value of angle may be selected to correspond to thetrip position. The trip position is generally considered to be therotational orientation at which the elevators (29 in FIG. 1A) extenddirectly toward the racking board (42 in FIG. 1A).

At 114, the displayed bottom three control windows (buttons) allow thesystem operator (e.g., the driller) to set the pipe handler stoppositions to selected rotational orientations. The numerical entrybuttons allow the operator to enter rotation stop positions in degreeswith respect to a reference, usually the trip position. The stoppositions could also be transmitted to the controller (FIG. 3) by anautomated pipe racking system. The display at 118 shows the actual pipehandler orientation in degrees. A control window or button on theoperator console at 116 may send a control signal to the controller(FIG. 3) to operate the pipe handler to rotate the pipe handlerorientation to zero degrees.

FIGS. 2A and 2B show oblique views of a top drive according to theinvention. The top drive 10 is shown in simplified form to illustratethe relevant parts of a system according to the invention. At 210 a pipehandler rotator gear rotates pipe handling components of the top driverotationally coupled to the rotator gear 210, including links 206,elevators 204 and link cylinders 208. The foregoing parts of the topdrive 10 are capable of rotating 360 degrees in either direction,independently of other operating parts of the top drive 10. The topdrive links 206 are typically coupled rotationally to the pipe handlerrotator gear 210. A pipe handler rotate motor 212 rotates the pipehandler rotator gear 210, and is in signal communication with thecontroller (FIG. 3). The links 206 may be coupled to the elevators 204that are used to lift the drill string (19 in FIG. 1A) from and lower itinto the wellbore when “tripping” pipe. In the present example, a rotaryposition encoder 202 (or a “rotational position sensor”) of any typeknown in the art may be used to measure the rotational orientation orposition of the pipe handler rotator gear 210. The links 206 may bemoved from a vertical orientation toward horizontal by the linkcylinders 208. The position of the link cylinders 208 may be measured bya sensor 208A, such as a linear position sensor (e.g. a linear variabledifferential transformer).

An example system configuration is shown in block diagram form in FIG.3. At 310 a general purpose programmable computer or programmable logiccontroller (PLC), for convenience referred to as a “controller”, mayprovide operating signals to operate certain parts of the systemdescribed with reference to FIGS. 2A and 2B, i.e., the pipe handlerrotate motor and the link cylinders. At 300, the operator console shownin FIG. 1 may be used so the operator can provide control input tocontrol operation of the system. At 302, the system controls may beseparate buttons or other physical switches, or may be part of a touchscreen as explained with reference to FIG. 1. Input from the rotaryposition encoder (202 in FIG. 2B) is shown conducted to the controller310 at 304. At 306, height of the top drive above the drill floor may bemeasured by a sensor (41 in FIG. 1A) in the drawworks or other part ofthe lifting system (see FIG. 1A). Extension of the link tilt cylindersas measured by the linear sensor (208A in FIG. 2B) may also be used asinput to the controller 310. During pipe tripping operations, thecontroller 310 may provide control signals to operate the pipe handlerrotate motor (212 in FIG. 2A) and receive signals from the rotaryencoder (202 in FIG. 2A) to move the pipe handler rotator gear (210 inFIG. 2A) to a selected rotary orientation, typically so that a “stand”of the drill string (19 in FIG. 1A) may be oriented toward the rackingboard, or removed from the racking board (42 in FIG. 1A). The controller310 may also provide a control signal 316 to operate the drawworks(shown as traveling block 12 in FIG. 1A) to move the top drive (10 inFIG. 1A) to a selected elevation above the drill floor. For example, thetop drive may be elevated to a height at which a stand of the drillstring may be moved toward the racking board (42 in FIG. 1A). The standof drill string may be then be manually unlatched by a “derrick man”, orremotely (314 in FIG. 3) unlatched by the driller from the elevators(204 in FIG. 2B) and racked into the racking board manually by thederrick man or automatically by an optional separate automated piperacking system (typically supplied by a different operator than the topdrive) 312. The pipe racking system may provide signals to thecontroller (310 in FIG. 3) to allow the automated pipe handler to rotateto the orientation requested by the automatic pipe racking system 312.Such orientation may be displayed (e.g., on the operator console screen114 in FIG. 1). As explained with reference to FIG. 1A, the elevationmay be measured by a suitable sensor (41 in FIG. 1A). The controller 310may then send a control signal to the link cylinders (208 in FIG. 2B) toextend toward horizontal so that the stand of drill string may be movedtoward the racking board (42 in FIG. 1A). In the present example, thecontroller 310 may be programmed to stop operation of the drawworks ifthe pipe handler rotate gear and/or the link cylinders are determined tobe in a position that might cause collision between components of thetop drive and the derrick or racking board.

A top drive and pipe handler automated control system according to thevarious aspects of the invention may save pipe trip time, increasesafety and reduce the possibility of damage to drilling unit components.

While the invention has been described with respect to a limited numberof embodiments, those skilled in the art, having benefit of thisdisclosure, will appreciate that other embodiments can be devised whichdo not depart from the scope of the invention as disclosed herein.Accordingly, the scope of the invention should be limited only by theattached claims.

What is claimed is:
 1. An automatic top drive positioning system,comprising: a top drive comprising a pipe handling system rotator gear,a drive motor rotationally coupled to the rotator gear and a rotationalposition sensor rotationally coupled to the rotator gear; and acontroller in signal communication with the rotator gear and the drivemotor, the controller configured to operate the drive motor toautomatically move the rotator gear to a selected rotational orientationbased on measurements from the rotational position sensor.
 2. Theautomatic top drive positioning system of claim 1 further comprisinglink cylinders coupled to elevator links coupled to the top drive, thelink cylinders configured to move elevator links coupled to the topdrive in a direction transverse to a direction of motion of the topdrive during drilling operations.
 3. The automatic top drive positioningsystem of claim 2 further comprising at least one sensor coupled to thelink cylinders in signal communication with the controller, at least onesensor configured to measure an elevation of the top drive above a drillfloor in signal communication with the controller, and wherein thecontroller is configured to automatically operate the rotator gear andthe link cylinders such that an elevation of the top drive and arotational orientation of the rotator gear prohibit interference betweenany part of the top drive and a drilling derrick.
 4. A method foroperating a top drive, comprising: measuring a rotational position of apipe handler rotate gear having elevator links rotationally coupledthereto; automatically rotating the pipe handler rotate gear such thatthe elevator links are disposed in a selected rotational orientationwith respect to a drilling derrick.
 5. The method of claim 4 furthercomprising measuring an elevation of the elevator links above a drillfloor and at least one of automatically rotating the pipe handler rotategear to an orientation such that interference between the elevator linksand the drilling derrick is avoided when the top drive is elevated inthe drilling derrick.
 6. The method of claim 4 further comprisingautomatically operating link extension cylinders to enable elevatorextension when the rotator gear is within a selected range of rotationalorientations.
 7. The method of claim 5 further comprising automaticallyretracting the link extension cylinders when the rotate gear in within aselected range of rotational orientation.